Trials of 5th Generation Mobile Communication Systems inIndoor Environments

Masaya Yamada

Assistant Director
Adaptive Communications research Laboratories
Advanced Telecommunications Research Institute International (ATR)

Nobuo Suzuki

Head
Dept. of Broadband Wireless Communications, Adaptive Communications research Laboratories
Advanced Telecommunications Research Institute International (ATR)

Hiroyuki Yokoyama

Director
Adaptive Communications research Laboratories
Advanced Telecommunications Research Institute International (ATR)■ Figure 1: Stadium application concept

1. Introduction
In anticipation of the realization of 5th generation (5G) mobilecommunication systems and new markets created using them, theMinistry of Internal Affairs and Communications (MIC) began
conducting 5G system trials starting in FY2017. In these trials,
the communications industry providing 5G and various otherindustries that will use 5G have cooperated, conducting tests in
six groups to ensure that the many and diverse applications andfeatures of 5G (high speed, many-connections, very low latency)
are all covered.
The authors participated in the fourth group (G IV),
collaborating with other agencies in 5G testing related to ultrahigh speed communication in indoor and enclosed environments.
This article reports on performance tests of 5G radio propagation
characteristics using the 28 GHz band and with 5G applications.

2. Evaluation test locations
The following three types of environment were selected forevaluation in indoor and enclosed environments.
Environment
Stadium

Location
Okinawa Cellular Stadium NahaRegion(2) Train station
To ensure much greater safety and security in train stations,a system is being studied, which transmits 4K or other highdefinition video using 5G features, processes it with an image
analysis application to detect dangerous articles or behavior thatneeds attention, and deals with it quickly and effectively. InFY2017, preliminary studies and evaluation were done on thebasic performance of an image analysis application for highdefinition video (2K and 4K class).
■ Figure 2: Train station application concept

Naha City, Okinawa
Prefecture

Inside train station Keikyu Railway, Haneda Airport Ota Ward, Tokyo
SchoolInternational Terminal Station

Maehara Elementary School

Koganei City, Tokyo

3. Application concepts and evaluation details
In these tests, 5G performance was evaluated in anticipateduse cases for various services and applications. The application
concepts at each of the test locations are described below.
(1) Stadium
Distribution of free-viewpoint video is being studied as
an application to develop entertainment in a stadium further,utilizing the ultra-high-speed and high capacity of 5G. In
FY2017, 28 GHz reception characteristics at spectator seats ina stadium were studied, and multiplexed high-resolution video
distribution tests were conducted.

(3) School
Use cases requiring the high-speed and high-capacity of 5G
are being studied as applications that can stimulate classroom
activity in an elementary school, such as simultaneously accessing
high-volume content using multiple terminals. In FY2017,preliminary studies and evaluations were done, examining theperformance of simultaneous access to high-volume content using
existing 4G networks.

New Breeze Autumn 201813

■ Figure 7: D etection performance of high-resolution
image analysis application■ Figure 3: S chool application concept

detection rate [%]distance

4. Test results(1) Stadium
The reception characteristics in the spectator seating at Okinawa Cellular Stadium were studied when transmitting in the
28 GHz band from the lighting tower near the third-base side.
28 GHz band propaga■ Figure 4: Map of propagation
tion losses at spectator
losses in the stadiumseats in the stadium weremeasured as shown in
Figure 4, generally demonstrating good receptionconditions.
T hen, antennas
transmitting 28 GHz
band 5G signals were
mounted on the thirdbase side lighting tower(Figure 5), and 25 5G terminals each were positioned in thespectator seats on both the first-base and third-base sides. Highdefinition video (2K and 4K class video) was distributed simultaneously from the transmitter, and all 50 5G terminals were able toreceive the video normally (Figure 6).
■ Figure 5: V iew of stadium and transmitter antenna
location
5GTransmitterantenna(3) School
In FY2017, to study the requirements for accessing highvolume content simultaneously from many terminals in anelementary school, we evaluated the performance of tasks suchas simultaneously uploading large content using multiple 4G
terminals.

■ Figure 8: P erformance evaluation system using 4G

In the performance tests, two classes of grade four students (36children/class) uploaded video and watched streaming video all atonce. As shown in Figure 9, up to 45 minutes was needed to upload a video. In separate ■ Figure 9: Distribution of timerequired for video
discussion with the eleupload (using 4G)
mentary school teachers,
they stated that ability
to upload videos within
one minute during classwould be desirable, so
there is a clear need forthe high-speed, highcapacity transmission
capabilities of 5G.

5. Conclusion■ Figure 6: High definition video reception tests using
5G terminals(2) Train station
In FY2017, the basic system for an application to detect people
by analyzing 2K and 4K-class high-definition video was built andevaluated. The evaluations compared performance in detecting
people when using 2K class and 4K class video. As shown in
Figure 7, people could be detected at approximately twice thedistance when analyzing 4K class video, relative to 2K class video,
demonstrating the utility of high-speed 5G transmission and its
ability to transmit 4K class high-definition video.

14

New Breeze Autumn 2018

This article describes performance evaluation tests conductedin FY2017 using applications anticipated to utilize the ultra-highspeed characteristics of 5G in the 28 GHz band, for indoor andenclosed environments. We plan to conduct further tests with 5G
in train stations and schools in the future.
Acknowledgements
These tests were conducted through a technical examination
service by MIC in FY2017 called “Contract of a service to study
technical requirements for 5th generation mobile communication
over 10 Gbps in indoor environments”
References[1]M IC, “5G Integration Testing Begins”, http://w w w.soumu.go.jp/menu _news/snews/01kiban14_02000297.html, May 2017.
[2]O kumura et al., “System Trials toward Actualization of 5th Generation Mobile
Communication System 5G,” MWE2017 Draft proceedings, 2017[3]Yamada et al., “Trials of 5th Generation Mobile Communication Systems in Indoor
Environments”, Proc. IEICE 2018 General Conference.